Data Protection and SnapMirror/SnapVault
This domain tests Snapshot copies, mirroring, backup retention, and recovery relationships.
Snapshots and policies
A Snapshot policy defines schedules and how many copies to retain. Snapshot copies are point-in-time and space-efficient, but they consume volume space as data changes. SnapMirror replicates to a destination for disaster recovery; SnapVault retains backups for longer-term recovery; a mirror-vault policy combines both. Relationships are created with snapmirror protect or the newer workflow, then initialized and monitored.
Operations
snapmirror initialize performs the baseline transfer; snapmirror update transfers the next Snapshot; snapmirror break makes the destination writable; snapmirror resync re-establishes the relationship after a break. SVM DR protects SVM configuration and volumes. Cloud Backup and SnapMirror to cloud extend protection off premises.
Worked example
A volume needs hourly mirroring for DR and 30 daily backups. Create a policy with a mirror rule using the hourly schedule and 7-day retention, plus a vault rule using daily and 30-day retention. Apply it to the relationship. If you instead use a mirror-only policy, the destination keeps only mirror copies and cannot satisfy the 30-day backup requirement.
Traps
Confusing SnapMirror with SnapVault retention; applying a policy whose rule labels do not match the relationship type; running snapmirror resync when initialize is required; and forgetting that Snapshot copies consume source volume space.